Stannous chloride dihydrate → HCID 18180307, compound

Participants

Reaction Steps

To a solution of 2.5 g (6.0 mmole) of toluene-4-sulfonic acid (2R)-8-(3-nitrilo-propenyl)-7-nitro-2,3-dihydro-benzo[1,4]dioxin-2-ylmethyl ester in 200 mL of ethyl acetate was added 6.8 g (30 mmole) of tin (II) chloride dihydrate and the mixture was refluxed under nitrogen for 5 hours. The solvent was then removed in vacuum and replaced with 250 mL of methanol. Concentrated HCl (5 mL) was added and the mixture was refluxed under a nitrogen atmosphere for 15 hours. The solvent was again removed in vacuum and 500 mL of saturated aqueous sodium bicarbonate added. This was extracted twice with 250 mL portions of ethyl acetate and the combined organics washed with 400 mL portions of water and saturated brine, dried over sodium sulfate, filtered and concentrated in vacuum. The residue was column chromatographed on silica gel with 5% methanol in chloroform as eluant to give 0.80 g of the (R)-enantiomer of the title compound as a yellow solid. 1H-NMR (CDCl3): doublet 8.0 δ (1 H); doublet 7.8 δ (2 H); doublet 7.3 δ (2 H); doublet 7.2 δ (1 H); doublet 7.1 δ (1 H); doublet 6.7 δ (1 H); multiplet 4.5 δ (1 H); multiplet 4.3 δ (3 H); doublet of doublets 4.1 δ (1 H); singlet 2.4 δ (3 H).

Provenance & Evidence